By dating the layer of "popcorn" on top of the art, the scientists came up with a minimum age and the date for the layer beneath the painting revealed the art's maximum age, the researchers said. Before becoming managing editor, Jeanna served as a reporter for Live Science and for about three years.

In addition to paintings, archaeologists have found other traces of human occupation inside these cavers: ochre "crayons," animal bones and shells. One hand stencil found in this region has a minimum age of more than 39,000 years old, said Maxime Aubert, of Griffith University, Gold Coast, Australia, in a video about the finding.

"This is the oldest hand stencil in the world," Aubert added in the video. Hand stencils, like the ones shown here, are created when artists spray paint or pigment over their hands.

More than 700 drawings have been discovered on the cave walls.

They are painted with bat guano (bat excrement) and represent hunting and dancing people as well as a large variety of animals.

These calcium carbonate deposits, which can take the form of "cave popcorn" (shown here) contain radioactive uranium.

That radioactive element provided a way for scientists to date the cave art.

Animals such as bisons, tigers, lions, and crocodiles have also been abundantly depicted in some caves.

The oldest paintings are considered to be 12,000 years old.

Jeanna has an English degree from Salisbury University, a Master's degree in biogeochemistry and environmental sciences from the University of Maryland, and a science journalism degree from New York University.